The practice of dentistry and dental or oral surgery frequently involves the production of small particles of debris in the patient's oral cavity, such as particles of dental amalgam or other restorative material, chips of teeth produced during extraction of a tooth or the drilling or other preparation of a tooth for restoration, or bits of debris removed from teeth during dental hygiene treatment. Furthermore, during dental procedures, small objects such as crowns, inlays, bridges, implants, etc. must often be introduced into the oral cavity. It is generally necessary that the dental patient be in an almost supine position, with the head back and the mouth opened wide, to allow the dental practitioner full access to the patients mouth and teeth. In this position, small particles produced in the oral cavity, or objects which fall or are accidentally dropped in the oral cavity may fall down the patient's throat and either be ingested into the esophagus or aspirated into the trachea.
Aspiration into the respiratory tract or lungs is particularly dangerous, since any foreign object carries with it the danger of infection and/or toxic or allergic reaction. Ingestion may also pose significant risk, since many of the products used in restorative dentistry may be toxic or allergenic in their uncured state, or as in the case of dental amalgam scrapings, present a long-term toxicity risk.
Dental practice regulations in most states require that a patient who has aspirated or swallowed a dropped crown, inlay, bridge, etc. undergo x-ray examination to determine where the object has lodged, and an ingested or inhaled dropped dental object may require follow-up medical care to insure against further medical problems.
Accidental ingestion or inhalation of dropped dental objects by a patient also adds significantly to the malpractice liability of the dental practitioner.
Furthermore, such objects as crowns, inlays and bridges cost hundreds of dollars to make, so that, even absent any harmful medical complications, accidental loss of these objects results in considerable economic loss to patient or dental practitioner and/or the distasteful task of recovering the object after it passes through the gastrointestinal tract.
For many dental procedures, dental dams, consisting of a thin sheet of latex rubber or similar material extending over the patient's mouth and clamped in a frame held against the patient's face, are used to prevent dental debris or objects from being swallowed or inhaled. Such dental dams are illustrated in Bolbolan, U.S. Pat. No. 5,931,673.
Typically, a hole or holes are cut or punched in the dental dam to permit one or more teeth to protrude through the dam, and a portion of the dam is inserted into the oral cavity and clamped around the teeth to be isolated. While such dams are effective in preventing ingestion or inhalation of dental debris or objects, and offer the added advantage of isolating teeth to be treated from the oral cavity, they are awkward and time-consuming to attach, confining to work in, and are poorly tolerated by many patients. The dams interfere with the patient's ability to breath through the mouth, which many patients feel the need of doing under the stress of a dental procedure, and makes it difficult to swallow. As a result, such dams can produce sensations of claustrophobia or choking in many patients. Such dental dams are generally used only for procedures requiring isolating one or more teeth from the oral cavity.
Intraoral dental dams to avoid some of the difficulties in the use of conventional dental dams are taught inter alia by Swan-Gett et al, U.S. Pat. No. 3,772,790; by Gray, U.S. Pat. No. 4,828,491; and by Bolbolan, U.S. Pat. No. 5,931,673. The dams taught in these patents would appear to be effective in preventing ingestion or inhalation of dental debris or objects, but would not allow breathing through the mouth. The aforementioned dams would also prevent excess saliva from draining from the mouth into the throat, where it could be swallowed.
Krygier et al, U.S. Pat. No. 4,889,491, teaches the use of a perforated throat shield held at the opening of the throat by a support member. The throat shield of Krygier et al is designed to prevent ingestion or inhalation of dental debris or objects while allowing the patient to breathe through the mouth, and also allows excess saliva to drain from the mouth to the throat. The throat shield of Krygier et al is complex, and would be relatively expensive to produce as a disposable device.
Neither the throat shield of Krygier et al nor the intraoral dental dams of Swan-Gett et al, Gray, or Bolbolan have found any substantial acceptance among dental practitioners, and neither the throat shield of Krygier et al nor any of the intraoral dams described appear to be commercially available.
In current dental practice, careful practitioners use common 2″ by 2″ gauze squares, partially unfolded to 4″ by 4″, placed in the back of the mouth to prevent ingestion or inhalation of dental debris or objects. These gauze squares allow the patient to breathe through the mouth, and allow excess saliva to drain into the throat. However, they quickly get wet with saliva, leading to collapse and lack of coverage of the throat, so they must be replaced frequently during dental procedures.
There is a need for a simple device which will prevent the ingestion or inhalation of dental debris or objects while allowing the patient to breathe freely through the mouth, and which will allow excess saliva to drain into the throat where it may be swallowed as often as the patient wishes. The device should be inexpensive, so that it may be disposable, to avoid the necessity for sterilization after use or the risk of transmitting disease.
The present invention provides such a device.